Fixing element for inserting into a longitudinal cavity of a carrier

ABSTRACT

A fixing element of plastic includes a foot part for insertion into an oblong hole of a carrier plate. The foot part includes a head and a shaft. The fixing element can be locked in the oblong hole after the insertion of the head by a quarter turn. The shaft includes a middle strut connected to the head. A shank is formed on each of the two edges of the middle strut at right angles and in opposite directions. A countershank is formed on each of the edges of the middle strut in opposite directions. The shank is elastically bent towards the middle strut during the screwing in of the shaft through the edge of the hole and after a quarter turn returns to its original position. Pressing ramps are formed on two outer ends of the head to prevent a rotation in the opposite direction.

RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.10/500,094 filed Jan. 24, 2005, which is a U.S. national phaseapplication under 371 of PCT Application No. PCT/EP02/14271 filed Dec.14, 2002, which claims priority of German Application No. 101 64 441.8filed Dec. 29, 2001.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to fixing elements consisting of plastic with afoot part for insertion into an oblong hole of a carrier plate. The footpart consists of a head corresponding to the edge of the oblong hole andof a shaft adapted to the width of the oblong hole. The fixing elementcan be locked in the oblong hole after the insertion of the head by aquarter turn under elastic deformation of the shaft. The shaft includesa middle strut connecting the head to the fixing element. The strut hasthe width of the oblong hole. A shank is formed on each of the two edgesof the middle strut at a right angle and in opposite directions in sucha manner that they are elastically bent towards the middle strut duringthe screwing in of the shaft through the edge of the oblong hole andafter a quarter turn they return to their original position as aconsequence of the elastic return force of the plastic and thus preventa rotation in the opposite direction.

2. Description of Related Art

Such fixing elements are known from U.S. Pat. No. 4,981,405. The designof the fixing element with two shanks formed on a shaft at a right angleand in opposite directions opposes a certain resistance to a turning ofthe fixing elements opposite the direction of screwing. The fixingelement advantageously reduces the risk of an unintentional loosening ofthe fixing element.

Other fixing elements with formed-on shanks are known from U.S. Pat. No.4,375,879 and U.S. Pat. No. 4,705,442.

DE 1181 007 describes a fixing element of this type designed as a screwand nut in which the nut shaft that can be inserted into the oblong holehas a width corresponding to the width of the oblong hole and has stopfaces running parallel to the screw axis. These stop faces work togetherwith corresponding faces in the oblong hole so that a rotation of thenut is prevented when the screw is tightened. This nut can be readilyslackened back again after the screw has been loosened and then can bewithdrawn through the oblong hole.

Furthermore, there are fixing elements with a foot part of theabove-cited type comparable to the nut and provided with a similarlydesigned shaft. However, since this foot part is not screwed down, thereis the danger that the fixing element can become loose again by anunintended rotary movement.

One advantage of the present fixing element is that it is distinguishedby an especially firm seat in the carrier plate.

The present invention is advantageous because it provides for a fixingelement with a head having pressing ramps on its two outer ends thatextend during screwing in over the edge of the oblong hole and othershanks formed on the free ends of the shanks.

The present invention is also advantageous because it provides for afixing element having a head with pressing ramps on its two outer endsthat extend during screwing in over the edge of the oblong hole and acountershank formed in the opposite direction on each of the two edgesof the middle strut.

The providing of the pressing ramps and of the other shanks andcountershanks results in an especially firm seat since the fixingelement is firmly connected to a carrier plate by the pressing rampsafter rotation in the direction of screwing in. Also, an especiallygreat resistance is provided to prevent to an undesired rotation of thefixing elements counter to the direction of screwing in by the othershanks and countershanks.

Other features and advantages of the present invention will be readilyappreciated, as the same becomes better understood, after reading thesubsequent description taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a side view of a fixing element with foot part foranchoring in an oblong hole.

FIG. 2 shows a section through the shaft with a view onto the headinserted in the oblong hole.

FIG. 3 shows the same section through the shaft during rotation.

FIG. 4 shows the same section through the shaft after a completedquarter turn.

FIG. 5 shows a sectional view of another fixing element with anothershaft design for connecting two plates.

FIG. 6 shows the fixing element of FIG. 5 in a side view.

FIG. 7 shows a section through the shaft with a view onto the headinserted in the oblong hole.

FIG. 8 shows the section through the shaft of FIG. 7 during therotation.

FIG. 9 shows the section through the shaft of FIG. 7 after a completedquarter turn.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The fixing element shown in FIGS. 1 to 4 consists of an upper part 1 forholding long structural components such as, e.g., cable bundles in aclamping manner. The fixing element also includes a foot part 3 formedon its bottom plate 2 in a one-piece manner that is designed to beinserted into an oblong hole 4 of a carrier plate 20. Foot part 3includes a head 5 adapted in its outer contour to an edge 6 of theoblong hole. The shaft 7 has the same width as the oblong hole. Head 5can be locked after having been inserted into oblong hole 4 by a quarterturn under elastic deformation of shaft 7.

The head 5 includes pressing ramps 8 on its two outer ends that slideduring screwing in over edge 6 of the oblong hole onto the back side ofthe carrier plate. The bottom plate includes lowest support ribs 9. Thebottom plate 2 is slightly curved for this purpose and flexes upward tosuch an extent, that the pressing of the lowest support ribs 9 causesthe pressing ramps 8 to slide under the carrier plate.

The shaft 7 includes a middle strut 10 connecting the head 5 to bottomplate 2. Shanks 12 are formed at a right angle and in oppositedirections on the two edges 11 of the middle strut 10. The shanks 12 areelastically bent toward the middle strut 10 during the screwing in ofthe shaft 7 through the edge 6 of the oblong hole (see FIGS. 3 and 8).After the quarter turn, the shanks 12 return to their original positionas a consequence of the elastic return force of the plastic (see FIGS. 4and 9). The shaft 7 cannot be turned in the opposite direction withoutdamaging the shaft 7, since shanks 12 cannot be pressed together andalso cannot otherwise yield.

In addition, the fixing element includes two other shanks 13 formed onthe free ends of the elastically deformable shanks 12, parallel tomiddle strut 10, and extending the length of the middle strut 10. Theseshanks have shoulders 14 extending in opposite directions on their freeends. The length of the shoulders is equal to the distance between themiddle strut 10 and shanks 13 extending parallel to it. This assuresthat the shanks 12 are clamped in after a quarter turn V between middlestrut 10 and edge 6 of oblong hole 4, and that elastically deformableshank 12 cannot yield laterally.

In another embodiment according to FIGS. 5 and 6, a fixing element forconnecting the two plates is shown with rotary handle 115 and resilientyielding support screen 116 on whose bottom plate 117 another shaftvariant is formed. It should be appreciated that like features have likereference numerals increased by 100.

In this example, the shaft includes a countershank 118 formed inopposite directions on the free edges 111 of the middle strut 110.Interval “A” of both shanks 112 and of countershanks 118 corresponds towidth “B” of oblong hole 104. Further, the countershank 118 isapproximately twice as thick as the elastically deformable shank 112. Inorder to reinforce the supporting contact of the elastic shank 112, ashoulder 119 is also formed at a right angle on the free end of theshark 112, similar to shanks 13 as previously described in FIG. 2.

The present invention has been described in an illustrative manner. Itis to be understood that the terminology which has been used is intendedto be in the nature of words of description rather than of limitation.

Many modifications and variations of the present invention are possiblein light of the above teachings. Therefore, within the scope of theappended claims, the present invention may be practiced other than asspecifically described.

1. A fixing element of plastic for insertion into an oblong hole of acarrier plate, comprising: a foot part including a head corresponding insize to the edge of the oblong hole; a shaft adapted to the width of theoblong hole, such that the fixing element can be locked in the oblonghole after the insertion of the head by a quarter turn under elasticdeformation of the shaft, wherein the shaft includes a middle strutconnecting to the head and the strut corresponds to the width of theoblong hole; a shank formed on each of the two edges of the middle strutat a right angle and in opposite directions, such that the shanks areadapted to be elastically bent towards the middle strut during thescrewing in of the shaft through the edge of the oblong hole and after aquarter turn return to their original position due to the elastic returnforce of the plastic; pressing ramps on two outer ends of the head forextending, during screwing in, over the edge of the oblong hole, toprevent a rotation in the opposite direction; and a countershank formedon each of the two edges of the middle strut in opposite directions. 2.The fixing element according to claim 1, wherein the overall length ofthe shanks, middle strut and countershank projecting at right anglescorresponds to the width of the oblong hole and each countershank isapproximately twice as thick as the associated, elastically deformableshank.